An aircraft steering apparatus is for operating a traveling direction of an aircraft when the aircraft travels on the ground such as a runway, and generally comprises an operation unit provided in a cockpit and an actuator driving the direction of a steered wheel (rolling direction) and the direction of a rudder of a vertical tail. The aircraft steering apparatus is provided with a control device controlling a steering operation and the control device is configured to control driving of the actuator in accordance with an operation amount signal output by the operation unit.
Currently, particularly in commercial aircrafts, an aircraft is generally operated by a pair of a main pilot and a co-pilot. In response to this circumstance, an aircraft steering apparatus is configured to have, as the operation unit in the cockpit, a steering handle for the mail pilot (main pilot steering handle), rudder pedals, and a steering handle for the co-pilot (co-pilot steering handle), as shown in FIG. 3 of Japanese Unexamined Patent Application Publication No. 2009-78781.
In such an aircraft steering apparatus, based on an operation amount corresponding to operation of any one of the main pilot steering handle, the rudder pedals and the co-pilot steering handle, the directions of the steered wheel and the rudder of the vertical tail are driven and controlled, thereby steering the traveling of the aircraft. It is noted that the steered wheel is a nose landing gear wheel of the aircraft in many cases; however, in a large aircraft, the steered wheel is a main landing gear wheel as well as a nose landing gear wheel in some cases.
The rudder pedals comprise a pair of a left operation pedal and a right operation pedal and mainly operate motion of the rudder of the vertical tail. For example, the rudder pedals are operated so that, when stepping down the left (right) rudder pedal, the rudder of the vertical tail is moved in the left (right) direction and a lift to the right (left) is generated, and thereby the nose is oriented to the left (right). In terms of operation safety, the rudder pedals are designed so that, even when the amount of stepping of the rudder pedals is maximum, the angle of the nose is not changed beyond a predetermined amount so as not to result in over control. Generally, in many cases, the main pilot mainly uses the rudder pedals for steering and uses the steering handle for steering when turning the nose largely.
Conventionally, the steering system of Patent Literature 2 has been suggested as a technique of steering traveling of an aircraft in accordance with a plurality of operation amounts output by an operation unit. In the steering system of Japanese Unexamined Patent Application Publication No. 2008-168656, a control unit 4 is configured to calculate a target angle of wheel based on output of a rudder pedal sensor 1 detecting an operation angle of rudder pedals and calculate a target angle of wheel based on output of a steering handle sensor 2 detecting an operation amount of a steering handle, and sum together the target angles to obtain a steering instruction angle (target steering angle).
According to the steering system of Japanese Unexamined Patent Application Publication No. 2008-168656, it is possible to perform a fine small-angle steering using the rudder pedals and a quick large-angle steering using the steering handle in parallel; therefore, a flexible steering suited to the occasion can be achieved.